Abstract: The laser plasma propulsion is a most prospective propulsion technology due to its unique advantages such as the high specific impulse, the large range of momentum thrust and the easily realized digital control. A review of the laser source, the theoretical model and the target material is made in this paper, including the progress of the laser plasma propulsion. For the laser source, the nanosecond and the microsecond laser pulses should be used together for their complementation nature. A two-dimensional model should be urgently developed, especially in a confined laser plasma propulsion. For the target material, the liquid as one of optimum target materials attracts much attention due to its higher coupling coefficient. To solve the problem of the low specific impulse due to the splashing behavior, the target properties, in particular, the viscosity are analyzed and a comparison is made among the target materials. A new energy-containing liquid material is discussed. Moreover, the parameter measurements of the coupling coefficient and the specific impulse are discussed. A new double probe beam device is introduced to measure the target momentum. Its measurement results are independent of the probe beam diameter and the target thickness.